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My smithii wasn't really out and about too much. If you're accustomed to keeping Peacocks or other Odontodactylids then you might be a bit disappointed. Smithii's are interactive but not like Peacocks in my experience.

A lot of conversation about mantis shrimp seems to be about making generalizations regarding the behavior of the various species. We all want to think that getting a particular species guarantees a certain level of activity and so forth but the truth seems to be that each individual mantis has a different temperament and activity level. It may be true that some species are better known than others for being active (for example, Peacocks > G. chiragra) but those generalizations do not always hold true. I once had a fairly active Chiragra and a much less active Smithii. But both of my Peacocks were active and full of personality.

Bottom line is to just try to create the most healthy tank environment for the mantis and usually they will respond positively.